High Speed Steel. Radial Tooth Face. These cutters may be resharpened repeatedly throughout the entire life of the cutter, without changing the original cutting form. Diametral Pitch indicates the number of teeth in a gear per inch of pitch diameter.

FOR EXAMPLE: to cut a 3" diameter gear with 24 teeth use a 8 Diametral Pitch, Number 5 cutter (24 teeth divided by 3"= 8 D.P., number 5 cutter is need to cut 24 teeth).